[gtk+/wip/css-icons: 1/6] css: Add support for -gtk-icontheme("icon-name")

[Benjamin Otte <otte src gnome org>]

commit 36d377eca0eebc3ed1125132c24c43b22348ebb4
Author: Benjamin Otte <otte redhat com>
Date:   Thu May 1 19:50:22 2014 +0200

    css: Add support for -gtk-icontheme("icon-name")
    
    This allows using icons from the icontheme as images in CSS. The
    reasoning is that this allows to give the image control about how it's
    scaled (by using the icon theme's scaling method. So we can get crisp
    images at different resolutions.

 gtk/Makefile.am                   |    2 +
 gtk/gtkcssimage.c                 |    2 +
 gtk/gtkcssimageicontheme.c        |  169 +++++++++++++++++++++++++++++++++++++
 gtk/gtkcssimageiconthemeprivate.h |   56 ++++++++++++
 4 files changed, 229 insertions(+), 0 deletions(-)
---
diff --git a/gtk/Makefile.am b/gtk/Makefile.am
index e3fa202..84ec352 100644
--- a/gtk/Makefile.am
+++ b/gtk/Makefile.am
@@ -455,6 +455,7 @@ gtk_private_h_sources =             \
        gtkcssenumvalueprivate.h        \
        gtkcssimagecrossfadeprivate.h   \
        gtkcssimagegradientprivate.h    \
+       gtkcssimageiconthemeprivate.h   \
        gtkcssimagelinearprivate.h      \
        gtkcssimageprivate.h    \
        gtkcssimagesurfaceprivate.h     \
@@ -702,6 +703,7 @@ gtk_base_c_sources =                \
        gtkcssimage.c           \
        gtkcssimagecrossfade.c  \
        gtkcssimagegradient.c   \
+       gtkcssimageicontheme.c  \
        gtkcssimagelinear.c     \
        gtkcssimagesurface.c    \
        gtkcssimageurl.c        \
diff --git a/gtk/gtkcssimage.c b/gtk/gtkcssimage.c
index 53b1c26..c5a336a 100644
--- a/gtk/gtkcssimage.c
+++ b/gtk/gtkcssimage.c
@@ -26,6 +26,7 @@
 /* for the types only */
 #include "gtk/gtkcssimagecrossfadeprivate.h"
 #include "gtk/gtkcssimagegradientprivate.h"
+#include "gtk/gtkcssimageiconthemeprivate.h"
 #include "gtk/gtkcssimagelinearprivate.h"
 #include "gtk/gtkcssimageurlprivate.h"
 #include "gtk/gtkcssimagescaledprivate.h"
@@ -423,6 +424,7 @@ gtk_css_image_get_parser_type (GtkCssParser *parser)
   } image_types[] = {
     { "url", _gtk_css_image_url_get_type },
     { "-gtk-gradient", _gtk_css_image_gradient_get_type },
+    { "-gtk-icontheme", _gtk_css_image_icon_theme_get_type },
     { "-gtk-scaled", _gtk_css_image_scaled_get_type },
     { "-gtk-win32-theme-part", _gtk_css_image_win32_get_type },
     { "linear-gradient", _gtk_css_image_linear_get_type },
diff --git a/gtk/gtkcssimageicontheme.c b/gtk/gtkcssimageicontheme.c
new file mode 100644
index 0000000..a681fe2
--- /dev/null
+++ b/gtk/gtkcssimageicontheme.c
@@ -0,0 +1,169 @@
+/*
+ * Copyright © 2012 Red Hat Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte gnome org>
+ */
+
+#include "config.h"
+
+#include "gtkcssimageiconthemeprivate.h"
+
+#include <math.h>
+
+#include "gtksettingsprivate.h"
+#include "gtkstyleproviderprivate.h"
+
+G_DEFINE_TYPE (GtkCssImageIconTheme, _gtk_css_image_icon_theme, GTK_TYPE_CSS_IMAGE)
+
+double
+gtk_css_image_icon_theme_get_aspect_ratio (GtkCssImage *image)
+{
+  /* icon theme icons only take a single size when requesting, so we insist on being square */
+  return 1.0;
+}
+
+static void
+gtk_css_image_icon_theme_draw (GtkCssImage        *image,
+                               cairo_t            *cr,
+                               double              width,
+                               double              height)
+{
+  GtkCssImageIconTheme *icon_theme = GTK_CSS_IMAGE_ICON_THEME (image);
+  GError *error = NULL;
+  GdkPixbuf *pixbuf;
+  gint size;
+
+  size = floor (MIN (width, height));
+  if (size <= 0)
+    return;
+
+  pixbuf = gtk_icon_theme_load_icon_for_scale (icon_theme->icon_theme,
+                                               icon_theme->name,
+                                               size,
+                                               icon_theme->scale,
+                                               GTK_ICON_LOOKUP_USE_BUILTIN,
+                                               &error);
+  if (pixbuf == NULL)
+    {
+      /* XXX: render missing icon image here? */
+      g_error_free (error);
+      return;
+    }
+
+  gdk_cairo_set_source_pixbuf (cr,
+                               pixbuf,
+                               (width - gdk_pixbuf_get_width (pixbuf)) / 2.0,
+                               (height - gdk_pixbuf_get_height (pixbuf)) / 2.0);
+  cairo_paint (cr);
+
+  g_object_unref (pixbuf);
+}
+
+
+static gboolean
+gtk_css_image_icon_theme_parse (GtkCssImage  *image,
+                            GtkCssParser *parser)
+{
+  GtkCssImageIconTheme *icon_theme = GTK_CSS_IMAGE_ICON_THEME (image);
+
+  if (!_gtk_css_parser_try (parser, "-gtk-icontheme(", TRUE))
+    {
+      _gtk_css_parser_error (parser, "Expected '-gtk-icontheme('");
+      return FALSE;
+    }
+
+  icon_theme->name = _gtk_css_parser_read_string (parser);
+  if (icon_theme->name == NULL)
+    return FALSE;
+
+  if (!_gtk_css_parser_try (parser, ")", TRUE))
+    {
+      _gtk_css_parser_error (parser, "Missing closing bracket at end of '-gtk-icontheme'");
+      return FALSE;
+    }
+
+  return TRUE;
+}
+
+static void
+gtk_css_image_icon_theme_print (GtkCssImage *image,
+                                GString     *string)
+{
+  GtkCssImageIconTheme *icon_theme = GTK_CSS_IMAGE_ICON_THEME (image);
+
+  g_string_append (string, "-gtk-icontheme(");
+  _gtk_css_print_string (string, icon_theme->name);
+  g_string_append (string, ")");
+}
+
+static GtkCssImage *
+gtk_css_image_icon_theme_compute (GtkCssImage             *image,
+                                  guint                    property_id,
+                                  GtkStyleProviderPrivate *provider,
+                                  int                      scale,
+                                  GtkCssComputedValues    *values,
+                                  GtkCssComputedValues    *parent_values,
+                                  GtkCssDependencies      *dependencies)
+{
+  GtkCssImageIconTheme *icon_theme = GTK_CSS_IMAGE_ICON_THEME (image);
+  GtkCssImageIconTheme *copy;
+  GtkSettings *settings;
+  GdkScreen *screen;
+
+  settings = _gtk_style_provider_private_get_settings (provider);
+  if (settings == NULL)
+    screen = gdk_screen_get_default ();
+  else
+    screen = _gtk_settings_get_screen (settings);
+
+  copy = g_object_new (GTK_TYPE_CSS_IMAGE_ICON_THEME, NULL);
+  copy->name = g_strdup (icon_theme->name);
+  copy->icon_theme = gtk_icon_theme_get_for_screen (screen);
+  copy->scale = scale;
+
+  return GTK_CSS_IMAGE (copy);
+}
+
+static gboolean
+gtk_css_image_icon_theme_equal (GtkCssImage *image1,
+                            GtkCssImage *image2)
+{
+  GtkCssImageIconTheme *icon_theme1 = GTK_CSS_IMAGE_ICON_THEME (image1);
+  GtkCssImageIconTheme *icon_theme2 = GTK_CSS_IMAGE_ICON_THEME (image2);
+
+  return g_str_equal (icon_theme1->name, icon_theme2->name);
+}
+
+static void
+_gtk_css_image_icon_theme_class_init (GtkCssImageIconThemeClass *klass)
+{
+  GtkCssImageClass *image_class = GTK_CSS_IMAGE_CLASS (klass);
+
+  image_class->get_aspect_ratio = gtk_css_image_icon_theme_get_aspect_ratio;
+  image_class->draw = gtk_css_image_icon_theme_draw;
+  image_class->parse = gtk_css_image_icon_theme_parse;
+  image_class->print = gtk_css_image_icon_theme_print;
+  image_class->compute = gtk_css_image_icon_theme_compute;
+  image_class->equal = gtk_css_image_icon_theme_equal;
+}
+
+static void
+_gtk_css_image_icon_theme_init (GtkCssImageIconTheme *icon_theme)
+{
+  icon_theme->icon_theme = gtk_icon_theme_get_default ();
+  icon_theme->scale = 1;
+}
+
diff --git a/gtk/gtkcssimageiconthemeprivate.h b/gtk/gtkcssimageiconthemeprivate.h
new file mode 100644
index 0000000..8482060
--- /dev/null
+++ b/gtk/gtkcssimageiconthemeprivate.h
@@ -0,0 +1,56 @@
+/*
+ * Copyright © 2012 Red Hat Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte gnome org>
+ */
+
+#ifndef __GTK_CSS_IMAGE_ICON_THEME_PRIVATE_H__
+#define __GTK_CSS_IMAGE_ICON_THEME_PRIVATE_H__
+
+#include "gtk/gtkcssimageprivate.h"
+#include "gtk/gtkicontheme.h"
+
+G_BEGIN_DECLS
+
+#define GTK_TYPE_CSS_IMAGE_ICON_THEME           (_gtk_css_image_icon_theme_get_type ())
+#define GTK_CSS_IMAGE_ICON_THEME(obj)           (G_TYPE_CHECK_INSTANCE_CAST (obj, 
GTK_TYPE_CSS_IMAGE_ICON_THEME, GtkCssImageIconTheme))
+#define GTK_CSS_IMAGE_ICON_THEME_CLASS(cls)     (G_TYPE_CHECK_CLASS_CAST (cls, 
GTK_TYPE_CSS_IMAGE_ICON_THEME, GtkCssImageIconThemeClass))
+#define GTK_IS_CSS_IMAGE_ICON_THEME(obj)        (G_TYPE_CHECK_INSTANCE_TYPE (obj, 
GTK_TYPE_CSS_IMAGE_ICON_THEME))
+#define GTK_IS_CSS_IMAGE_ICON_THEME_CLASS(obj)  (G_TYPE_CHECK_CLASS_TYPE (obj, 
GTK_TYPE_CSS_IMAGE_ICON_THEME))
+#define GTK_CSS_IMAGE_ICON_THEME_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), 
GTK_TYPE_CSS_IMAGE_ICON_THEME, GtkCssImageIconThemeClass))
+
+typedef struct _GtkCssImageIconTheme           GtkCssImageIconTheme;
+typedef struct _GtkCssImageIconThemeClass      GtkCssImageIconThemeClass;
+
+struct _GtkCssImageIconTheme
+{
+  GtkCssImage parent;
+
+  GtkIconTheme *icon_theme;
+  gint scale;
+  char *name;
+};
+
+struct _GtkCssImageIconThemeClass
+{
+  GtkCssImageClass parent_class;
+};
+
+GType          _gtk_css_image_icon_theme_get_type             (void) G_GNUC_CONST;
+
+G_END_DECLS
+
+#endif /* __GTK_CSS_IMAGE_ICON_THEME_PRIVATE_H__ */